How to ensure your irrigation system does not break down in winter
15th January, 2012 by admin
The spring of 2011 was a boom time for UK irrigation service companies. Many reported a huge upturn in business at a time when the general golf course irrigation contracting trend was quite the opposite. The reason is very simple. A significant number of systems had been damaged during the winter.
Those winter months were, for many parts of the UK, a prolonged period of extreme cold. This is all too often a precursor to irrigation system damage as the water in pumps, tanks, pipes and valve assemblies freezes. In some years, there is time in the spring to resolve the problems before the need to irrigate. Last year wasn’t like that, and the early and lengthy dry spell created an irrigation demand that caught out some clubs. No doubt budgetary constraints had an impact with service contracts covering system winterisation being cancelled and course managers had to take on the work themselves rather than bring in an irrigation company.
As many clubs learnt, the operational and financial implications of failing to adequately protect components could be serious and far reaching.
The main objective of how an irrigation system should be prepared for the winter is to get as much water as possible out of the system thereby eliminating the possibility of damage by freezing water.
Above ground equipment such as pumps and pump / tank connecting pipework are most vulnerable. They should be drained down and drain valves should be left partially open or taken out to prevent any long term water accumulation. All pump houses should be equipped with heaters set to maintain the interior temperature. Tank rising mains need to be drained and isolated from the incoming water supply. The circular sectional steel tanks butyl or EPDM liner that are the most commonly used must not be fully drained, as they require the weight of water to prevent them being damaged by high winds. The water level should be dropped however, so that float on the incoming main ball valve in the tank hangs down in order to keep the valve in the open position. In addition, keep tank roofs clear of excessive snow accumulation.
When looking at underground components, a good pipework system will have a number of drain points at low points around the course. These will normally be either in access chambers or at stream crossings. Once the water has been drained, partially close the valves to prevent ground water, soil, insects and so on getting into the pipework. This is about as much as can be done, however if you are unhappy with the number of drain points, the provision of additional ones could be a worthwhile winter task.
With the specialist components, some irrigation companies will recommend setting the controller to power up the solenoid coils at regular intervals during the winter thus reducing condensation and damp conditions. Others will suggest that the controller is isolated from the field cables to reduce the possibility of damage to it from a lightning strike resulting in a power surge along the cable and back to the controller. It’s a case of talking to the system supplier or service company and seeking their advice.
On the subject of irrigation contracting and servicing companies, the vast majority offer system winterisation services and employing them for this work will ensure the correct procedures are followed. Annual service contracts are also worth considering as advanced financial provision can be made.
There are potential safety issues when maintaining irrigation systems. The combination of water and electricity is an unwelcome mix and when the water is at high pressure, the dangers are further heightened. Any work on the electric components of pumps, pump control panels and the high voltage side of irrigation controllers must be carried out by a suitably qualified electrician. On the hydraulic side, a full understanding of the possible dangers of high pressure water systems is essential, including how to determine actual system pressures. These pressures can be dynamic, that is when the system is being pressurised by the pumping system, or static, when a residual pressure occurs and height differentials across the course allow pressure to be maintained or increased even when the pump system is not operating.
In summary, preparing golf course irrigation systems for cold weather is a relatively straightforward exercise and a methodical approach and common sense will go a long way to a successful outcome. This must be combined with a comprehensive safety procedure. The employment of a reputable irrigation contractor, with appropriately qualified personnel, will ensure the system is fully protected and will offer the opportunity to fully assess the system’s condition with the possibility of any remedial, replacement or repair work being carried out during the winter in readiness for the irrigation season.
Do-it-yourself or bring in a specialist company, as always, it’s your choice!
Graeme Francis, a sportsturf irrigation expert with experience in both the Middle East and in the UK, is sports sales manager at Revaho UK
